Flame retardant compositions

ABSTRACT

Organic polymer substrates, for example polyolefins such as polypropylene, can be made flame retardant by the incorporation of a mixture of (i) at least one melamine based flame retardant and (ii) at least one flame retardant selected from the group consisting of the organohalogen and phosphorus containing flame retardants. Further optional flame retardants include antimony compounds and sterically hindered amines.

This application claims the benefit under 35 USC 119(e) of U.S.Provisional Application Ser. No. 60/423,678, filed Nov. 4, 2002.

The instant invention pertains to a novel method of flame retarding apolymeric substrate by adding thereto an effective flame retardingamount of a mixture of at least one melamine based flame retardant andat least one flame retardant selected from the group consisting of theorganohalogen and phosphorus containing flame retardants.

The instant invention in particular pertains to a method of flameretarding polyolefins such as polypropylene and polyethylene.

BACKGROUND OF THE INVENTION

U.S. Pat. No. 4,504,611 teaches flame retardant polyamide comprisingzinc borate, melamine cyanurate and certain organohalogens.

JP 54113647 discloses flame retardant polyamide comprising melaminecyanurate and DBDPO.

GB 2085898 discloses flame retardant polyolefin comprising aromaticbromo hydrocarbon (DBDPO), an antimony or bismuth compound, an organiccompound, and a triazine derivative (e.g. melamine).

JP 57070152 teaches flame retardant epoxy resins which contain antimonytrioxide, an orgaonobromine compound and a melamine-cyanuric acidadduct.

JP 58101128 teaches flame retardant epoxy resin, phenol resin, thermosetpolyester resin or polyurethane resin, which contain antimony trioxide,organohalogen compound, melamine-cyanuric acid product,melamine-phosphoric acid product and melamine-molybdic acid product.

U.S. Pat. No. 5,356,568 teaches flame retardant coatings that comprisephosphorus-containing material (e.g. melamine phosphate) and ahalogen-containing material (e.g. chlorinated paraffin).

JP 10176095 discloses flame retardant polystyrene comprisingorganohalogen compounds and ammonium polyphosphates and/or triazinephosphates (e.g. melamine phosphate) and a drip-proof agent.

It has been found that polymers with good flame retardant properties,for example polyolefins, are prepared when a melamine based flameretardant is added thereto together with an organohalogen flameretardant or a phosphorus containing flame retardant.

DETAILED DISCLOSURE

The instant invention pertains to a flame retardant polymer compositionwhich comprises

-   -   (a) an organic polymer substrate and    -   (b) an effective flame retarding amount of a mixture of        -   (i) at least one melamine based flame retardant and        -   (ii) at least one flame retardant selected from the group            consisting of the organohalogen and the phosphorus            containing flame retardants.

The mixture of (i) and (ii) is in many instances synergistic towardsproviding flame retardancy.

The compositions of this invention may further include flame retardantfillers and/or conventional fillers. Flame-retardant fillers are knownin the art and are selected from the group consisting of magnesiumhydroxide, alumina trihydrate and zinc borate. Flame-retardant fillersare inorganic compounds employed for flame-retardant properties, and athigh enough levels to be considered “filler”. Conventional fillers suchas talc, calcium carbonate and the like are normally employed forinstance for flow properties in order to reduce the spread of flamingdroplets (not flame-retardant per se).

The compositions of this invention may further include nano-scaledfillers. Nano-scaled fillers are also referred to as “nanoclays” aredisclosed for example in U.S. Pat. Nos. 5,853,886 and 6,020,419, therelevant disclosures of which are hereby incorporated by reference.

Nano-scaled fillers of the present invention are for examplephyllosilicates or smectite clays, for example organophilicphyllosilicates, naturally occuring phyllosilicates, syntheticphyllosilicates or a mixture of such phyllosilicates. The presentnano-scaled fillers are for example montmorillonites, bentonites,beidellites, hectorites, saponites or stevensites.

The present compositions may further advantageously include antimonycompounds such as antimony trioxide (Sb₂O₃) or antimony pentoxide(Sb₂O₅). The antimony compounds may be present from about 0.5% to about8% by weight, based on the weight of the polymer substrate. For example,the antimony compounds may be present from about 1% to about 6% byweight, or from about 2% to about 5% by weight, based on the weight ofthe polymer substrate. For example, the antimony compounds may bepresent at about 2%, 3%, 4% or 5% by weight, based on the weight of thepolymer substrate.

The present compositions may further advantageously include stericallyhindered amine stabilizers. The sterically hindered amines may bepresent from about 0.1% to about 10% by weight, based on the weight ofthe polymer substrate.

In particular, the present compositions may include both antimonycompounds and sterically hindered amine stabilizers.

The present compositions may advantageously include acid scavengers.Acid scavengers are for example hydrotalcites and amorphous basicaluminum magnesium carbonates, such as those described in U.S. Pat. Nos.4,427,816, 5,106,898 and 5,234,981, the relevant disclosures of whichare hereby incorporated by reference. Hydrotalcite is, also known ashycite or DHT4A.

Hydrotalcites are natural or synthetic. The natural hydrotalcite is heldto possess a structure Mg₆Al₂(OH)₁₆CO₃.4 H₂O. A typical empiricalformula of a synthetic hydrotalcite isAl₂Mg_(4.35)OH_(11.36)CO_(3(1.67)).x H₂O. Examples of the syntheticproduct include: Mg_(0.7)Al_(0.3)(OH)₂(CO₃)_(0.15).0.54 H₂O,Mg_(4.5)Al₂(OH)₁₃CO₃.3.5 H₂O and Mg_(4.2)Al(OH)_(12.4)CO₃.

The present compositions meet requirements of UL 1694 Tests forFlammability of Small Polymeric Component Materials, 2002. The presentcompositions also meet requirements of UL 94 Tests for Flammability ofPlastic Materials for Parts in Devices and Appliances.

The present compositions also exhibit excellent physical properties asexhibited by tensile strength and/or impact strength.

The present compositions do not require organic radical sources to meetfor example a V-0, V-1 or a V-2 threshold according to UL 94, or to meeta SC-0, SC-1 or SC-2 level according to UL 1694. The organic radicalsources are for example compounds of formula (1) according to GB2085898, for example (2,3-dimethyl-2,3-diphenyl)-hexane or -butane.

Meeting V-0, V-1 or V-2 according to UL 94, or meeting SC-0, SC-1 orSC-2 according to UL 1694 is considered “passing” UL 94 or UL 1694respectively.

The compounds of formula (1) of GB 2085898 are

where R=CH₃ or C₂H₅, R′=CH₃ and R″=C₆H₅.

Accordingly, the present compositions comprise essentially no organicradical sources, or comprise no organic radical sources.

Both clear and pigmented polymer compositions, for example pigmentedpolypropylene compositions, meet V-0, V-1 or V-2 according to UL 94 orSC-0, SC-1 or SC-2 according to UL 1694.

The present compositions also meet V-0, V-1 or V-2 according to UL-94 orSC-0, SC-1 or SC-2 according to UL 1694 after weathering exposure(ultraviolet light exposure), for example after exposure to 1000 hoursin a xenon arc WeaterOmeter, Atlas Cl 65A xenon arc WeaterOmeter, ASTMG26 test method A. After exposure, the compositions also retain at least75% of izod impact strength and tensile strength.

The present compositions also meet V-0, V-1 or V-2 or SC-0, SC-1 or SC-2performance levels according to UL 94 or UL 1694 respectively, afterexposure to water, for example after immersion in water for 7 days at70° C. After water immersion, the samples also retain at least 50% ofizod impact strength and tensile strength.

The present compositions also meet V-0, V-1 or V-2 or SC-0, SC-1 or SC-2performance levels according to UL 94 or UL 1694 respectively, afterthermal exposure, for example after oven aging at different elevatedtemperatures (130, 140, 150 and 160° C. for 9000 hrs, 5000 hrs, 2500 hrsand 1000 hrs, respectively), or at 90C for 2000 hours. The oven is aregular air forced oven. After the exposure, the samples also retain atleast 65% of physical properties such as izod impact and tensilestrength.

The compositons are for example polypropylene homopolyer plaquescomprising the present flame retardant additives, for example 1.6 mmplaques. The polypropylene plaques are clear or pigmented, for instancewhite or green pigmented.

Polymer Substrate (a)

The polymer substrate of component (a) is any of a wide variety ofpolymer types including polyolefins, polystyrenics, and PVC. Forexample, the polymer substrate may be selected from the group of resinsconsisting of the polyolefins, the thermoplastic olefins, styrenicpolymers and copolymers, ABS and polymers which contain hetero atoms,double bonds or aromatic rings. Specific embodiments are where component(a) is polypropylene, polyethylene, thermoplastic olefin (TPO), ABS orhigh impact polystyrene.

For example, the polymer substrate is selected from the group of resinsconsisting of the polyolefins, the thermoplastic olefins, styrenicpolymers and copolymers, and ABS.

Another embodiment of the present invention is where the polymersubstrate is selected from the group consisting of polypropylene,polyethylene, thermoplastic olefin (TPO), ABS and high impactpolystyrene.

For instance, the polymer substrate is polypropylene, polyethylene orthermoplastic olefin (TPO). Organic polymers of component A are forexample thermoplastic polymers such as polyolefins like polyethylene,polypropylene or copolymers thereof. The thermoplastic polymer is forexample polypropylene.

Further examples for organic polymers (component A) are:

1. Polymers of monoolefins and diolefins, for example polypropylene,polyisobutylene, polybut-1-ene, poly-4-methylpent-1-ene,polyvinylcyclohexane, polyisoprene or polybutadiene, as well as polymersof cycloolefins, for instance of cyclopentene or norbornene,polyethylene (which optionally can be crosslinked), for example highdensity polyethylene (HDPE), high density and high molecular weightpolyethylene (HDPE-HMW), high density and ultrahigh molecular weightpolyethylene (HDPE-UHMW), medium density polyethylene (MDPE), lowdensity polyethylene (LDPE), linear low density polyethylene (LLDPE),(VLDPE) and (ULDPE).

-   Polyolefins, i.e. the polymers of monoolefins exemplified in the    preceding paragraph, for example polyethylene and polypropylene, can    be prepared by different, and especially by the following, methods:    -   a) radical polymerisation (normally under high pressure and at        elevated temperature).    -   b) catalytic polymerisation using a catalyst that normally        contains one or more than one metal of groups IVb, Vb, VIb or        VIII of the Periodic Table. These metals usually have one or        more than one ligand, typically oxides, halides, alcoholates,        esters, ethers, amines, alkyls, alkenyis and/or aryls that may        be either π- or σ-coordinated. These metal complexes may be in        the free form or fixed on substrates, typically on activated        magnesium chloride, titanium(III) chloride, alumina or silicon        oxide. These catalysts may be soluble or insoluble in the        polymerisation medium. The catalysts can be used by themselves        in the polymerisation or further activators may be used,        typically metal alkyls, metal hydrides, metal alkyl halides,        metal alkyl oxides or metal alkyloxanes, said metals being        elements of groups Ia, IIa and/or IIIa of the Periodic Table.        The activators may be modified conveniently with further ester,        ether, amine or silyl ether groups. These catalyst systems are        usually termed Phillips, Standard Oil Indiana, Ziegler (-Natta),        TNZ (DuPont), metallocene or single site catalysts (SSC).

2. Mixtures of the polymers mentioned under 1), for example mixtures ofpolypropylene with polyisobutylene, polypropylene with polyethylene (forexample PP/HDPE, PP/LDPE) and mixtures of different types ofpolyethylene (for example LDPE/HDPE).

3. Copolymers of monoolefins and diolefins with each other or with othervinyl monomers, for example ethylene/propylene copolymers, linear lowdensity polyethylene (LLDPE) and mixtures thereof with low densitypolyethylene (LDPE), propylene/but-1-ene copolymers,propylene/isobutylene copolymers, ethylene/but-1-ene copolymers,ethylene/hexene copolymers, ethylene/methylpentene copolymers,ethylene/heptene copolymers, ethylene/octene copolymers,ethylene/vinylcyclohexane copolymers, ethylene/cycloolefin copolymers(e.g. ethylene/norbornene like COC), ethylene/1-olefins copolymers,where the 1-olefin is generated in-situ; propylene/butadiene copolymers,isobutylene/isoprene copolymers, ethylene/vinylcyclohexene copolymers,ethylene/alkyl acrylate copolymers, ethylene/alkyl methacrylatecopolymers, ethylene/vinyl acetate copolymers or ethylene/acrylic acidcopolymers and their salts (ionomers) as well as terpolymers of ethylenewith propylene and a diene such as hexadiene, dicyclopentadiene orethylidene-norbornene; and mixtures of such copolymers with one anotherand with polymers mentioned in 1) above, for examplepolypropylene/ethylene-propylene copolymers, LDPE/ethylene-vinyl acetatecopolymers (EVA), LDPE/ethylene-acrylic acid copolymers (EAA),LLDPE/EVA, LLDPE/EAA and alternating or random polyalkylene/carbonmonoxide copolymers and mixtures thereof with other polymers, forexample polyamides.

4. Hydrocarbon resins (for example C₅–C₉) including hydrogenatedmodifications thereof (e.g. tackifiers) and mixtures of polyalkylenesand starch.

Homopolymers and copolymers from 1. )–4. ) may have any stereostructureincluding syndiotactic, isotactic, hemi-isotactic or atactic; forexample atactic polymers. Stereoblock polymers are also included.

5. Polystyrene, poly(p-methylstyrene), poly(α-methylstyrene).

6. Aromatic homopolymers and copolymers derived from vinyl aromaticmonomers including styrene, α-methylstyrene, all isomers of vinyltoluene, especially p-vinyltoluene, all isomers of ethyl styrene, propylstyrene, vinyl biphenyl, vinyl naphthalene, and vinyl anthracene, andmixtures thereof. Homopolymers and copolymers may have anystereostructure including syndiotactic, isotactic, hemi-isotactic oratactic; for example atactic polymers. Stereoblock polymers are alsoincluded.

6a. Copolymers including aforementioned vinyl aromatic monomers andcomonomers selected from ethylene, propylene, dienes, nitriles, acids,maleic anhydrides, maleimides, vinyl acetate and vinyl chloride oracrylic derivatives and mixtures thereof, for example styrene/butadiene,styrene/acrylonitrile, styrene/ethylene (interpolymers), styrene/alkylmethacrylate, styrene/butadiene/alkyl acrylate, styrene/butadiene/alkylmethacrylate, styrene/maleic anhydride, styrene/acrylonitrile/methylacrylate; mixtures of high impact strength of styrene copolymers andanother polymer, for example a polyacrylate, a diene polymer or anethylene/propylene/diene terpolymer; and block copolymers of styrenesuch as styrene/butadiene/styrene, styrene/isoprene/styrene,styrene/ethylene/butylene/styrene or styrene/ethylene/propylene/styrene.

6b. Hydrogenated aromatic polymers derived from hydrogenation ofpolymers mentioned under 6.), especially includingpolycyclohexylethylene (PCHE) prepared by hydrogenating atacticpolystyrene, often referred to as polyvinylcyclohexane (PVCH).

6c. Hydrogenated aromatic polymers derived from hydrogenation ofpolymers mentioned under 6a.).

Homopolymers and copolymers may have any stereostructure includingsyndiotactic, isotactic, hemi-isotactic or atactic; for example atacticpolymers. Stereoblock polymers are also included.

7. Graft copolymers of vinyl aromatic monomers such as styrene orα-methylstyrene, for example styrene on polybutadiene, styrene onpolybutadiene-styrene or polybutadiene-acrylonitrile copolymers; styreneand acrylonitrile (or methacrylonitrile) on polybutadiene; styrene,acrylonitrile and methyl methacrylate on polybutadiene; styrene andmaleic anhydride on polybutadiene; styrene, acrylonitrile and maleicanhydride or maleimide on polybutadiene; styrene and maleimide onpolybutadiene; styrene and alkyl acrylates or methacrylates onpolybutadiene; styrene and acrylonitrile on ethylene/propylene/dieneterpolymers; styrene and acrylonitrile on polyalkyl acrylates orpolyalkyl methacrylates, styrene and acrylonitrile on acrylate/butadienecopolymers, as well as mixtures thereof with the copolymers listed under6), for example the copolymer mixtures known as ABS, MBS, ASA or AESpolymers.

8. Halogen-containing polymers such as polychloroprene, chlorinatedrubbers, chlorinated and brominated copolymer of isobutylene-isoprene(halobutyl rubber), chlorinated or sulfochlorinated polyethylene,copolymers of ethylene and chlorinated ethylene, epichlorohydrin homo-and copolymers, especially polymers of halogen-containing vinylcompounds, for example polyvinyl chloride, polyvinylidene chloride,polyvinyl fluoride, polyvinylidene fluoride, as well as copolymersthereof such as vinyl chloride/vinylidene chloride, vinyl chloride/vinylacetate or vinylidene chloride/vinyl acetate copolymers.

9. Polymers derived from α,β-unsaturated acids and derivatives thereofsuch as polyacrylates and polymethacrylates; polymethyl methacrylates,polyacrylamides and polyacrylonitriles, impact-modified with butylacrylate.

10. Copolymers of the monomers mentioned under 9) with each other orwith other unsaturated monomers, for example acrylonitrile/butadienecopolymers, acrylonitrile/alkyl acrylate copolymers,acrylonitrile/alkoxyalkyl acrylate or acrylonitrile/vinyl halidecopolymers or acrylonitrile/alkyl methacrylate/butadiene terpolymers.

11. Polymers derived from unsaturated alcohols and amines or the acylderivatives or acetals thereof, for example polyvinyl alcohol, polyvinylacetate, polyvinyl stearate, polyvinyl benzoate, polyvinyl maleate,polyvinyl butyral; polyallyl phthalate or polyallyl melamine; as well astheir copolymers with olefins mentioned in 1) above.

12. Homopolymers and copolymers of cyclic ethers such as polyalkyleneglycols, polyethylene oxide, polypropylene oxide or copolymers thereofwith bisglycidyl ethers.

13. Polyacetals such as polyoxymethylene and those polyoxymethyleneswhich contain ethylene oxide as a comonomer; polyacetals modified withthermoplastic polyurethanes, acrylates or MBS.

14. Polyphenylene oxides and sulfides, and mixtures of polyphenyleneoxides with styrene polymers or polyamides.

15. Polyurethanes derived from hydroxyl-terminated polyethers,polyesters or polybutadienes on the one hand and aliphatic or aromaticpolyisocyanates on the other, as well as precursors thereof.

16. Polyamides and copolyamides derived from diamines and dicarboxylicacids and/or from aminocarboxylic acids or the corresponding lactams,for example polyamide 4, polyamide 6, polyamide 6/6, 6/10, 6/9, 6/12,4/6, 12/12, polyamide 11, polyamide 12, aromatic polyamides startingfrom m-xylene diamine and adipic acid; polyamides prepared fromhexamethylenediamine and isophthalic or/and terephthalic acid and withor without an elastomer as modifier, for examplepoly-2,4,4,-trimethylhexamethylene terephthalamide or poly-m-phenyleneisophthalamide; and also block copolymers of the aforementionedpolyamides with polyolefins, olefin copolymers, ionomers or chemicallybonded or grafted elastomers; or with polyethers, e.g. with polyethyleneglycol, polypropylene glycol or polytetramethylene glycol; as well aspolyamides or copolyamides modified with EPDM or ABS; and polyamidescondensed during processing (RIM polyamide systems).

17. Polyureas, polyimides, polyamide-imides, polyetherimids,polyesterimids, polyhydantoins and polybenzimidazoles.

18. Polyesters derived from dicarboxylic acids and diols and/or fromhydroxycarboxylic acids or the corresponding lactones, for examplepolyethylene terephthalate, polybutylene terephthalate,poly-1,4-dimethylolcyclohexane terephthalate, polyalkylene naphthalate(PAN) and polyhydroxybenzoates, as well as block copolyether estersderived from hydroxyl-terminated polyethers; and also polyestersmodified with polycarbonates or MBS.

19. Polycarbonates and polyester carbonates.

20. Polyketones.

21. Polysulfones, polyether sulfones and polyether ketones.

22. Blends of the aforementioned polymers (polyblends), for examplePP/EPDM, Polyamide/EPDM or ABS, PVC/EVA, PVC/ABS, PVC/MBS, PC/ABS,PBTP/ABS, PC/ASA, PC/PBT, PVC/CPE, PVC/acrylates, POM/thermoplastic PUR,PC/thermoplastic PUR, POM/acrylate, POM/MBS, PPO/HIPS, PPO/PA 6.6 andcopolymers, PA/HDPE, PA/PP, PA/PPO, PBT/PC/ABS or PBT/PET/PC.

Flame Retardants of Component (b)

The melamine based flame retardants are for example:

-   -   melamine cyanurate,    -   melamine borate,    -   melamine phosphates,    -   melamine polyphosphates,    -   melamine pyrophosphates,    -   melamine ammonium polyphosphates and    -   melamine ammonium pyrophosphates.

Oganohalogen flame retardants are for example:

-   -   Chloroalkyl phosphate esters (ANTIBLAZE® AB-100, Albright &        Wilson; FYROL® FR-2, Akzo Nobel),    -   tris(2-chloroethyl)phosphate    -   polybrominated diphenyl oxide (DE-60F, Great Lakes Corp.),    -   decabromodiphenyl oxide (DBDPO; SAYTEX® 102E),    -   tris[3-bromo-2,2-bis(bromomethyl)propyl]phosphate (PB 370®, FMC        Corp.),    -   tris(2,3-dibromopropyl)phosphate    -   tris(2,3-dichloropropyl)phosphate,    -   chlorendic acid,    -   tetrachlorophthalic acid,    -   tetrabromophthalic acid,    -   bis-(N,N′-hydroxyethyl)tetrachlorphenylene diamine,    -   poly-β-chloroethyl triphosponate mixture    -   bis(2,3-dibromopropyl ether) of tetrabromobisphenol A (PE68),    -   brominated epoxy resin,    -   ethylene-bis(tetrabromophthalimide) (SAYTEX® BT-93),    -   bis(hexachlorocyclopentadieno)cyclooctane (DECLORANE PLUS®),    -   chlorinated paraffins,    -   octabromodiphenyl ether,    -   hexachlorocyclopentadiene derivatives,    -   1,2-bis(tribromophenoxy)ethane (FF680),    -   tetrabromo-bisphenol A (SAYTEX® RB100),    -   ethylene bis-(dibromo-norbornanedicarboximide) (SAYTEX® 451),    -   bis-(hexachlorocyclopentadieno)cyclooctane,    -   PTFE    -   tris-(2,3-dibromopropyl)-isocyanurate, and    -   ethylene-bis-tetrabromophthalimide.

The phosphorus containing flame retardants are for example:

-   -   Tetraphenyl resorcinol diphosphite (FYROLFLEX® RDP, Akzo Nobel),    -   triphenyl phosphate,    -   trioctyl phosphate,    -   tricresyl phosphate,    -   tetrakis(hydroxymethyl)phosphonium sulfide,    -   diethyl-N,N-bis(2-hydroxyethyl)-aminomethyl phosphonate,    -   hydroxyalkyl esters of phosphorus acids,    -   ammonium polyphosphate (APP) or (HOSTAFLAM® AP750),    -   resorcinol diphosphate oligomer (RDP),    -   phosphazene flame retardants,    -   ethylenediamine diphosphate (EDAP),    -   phosphonates and their metal salts and    -   phosphinates and their metal salts.

Boric acid may be included as a further flame retardant.

The halogenated flame retardants useful in the present invention may beselected from organic aromatic halogenated compounds such as halogenatedbenzenes, biphenyls, phenols, ethers or esters thereof, bisphenols,diphenyloxides, aromatic carboxylic acids or polyacids, anhydrides,amides or imides thereof; organic cycloaliphatic or polycycloaliphatichalogenated compounds; and organic aliphatic halogenated compounds suchas halogenated paraffins, oligo- or polymers, alkylphosphates oralkylisocyanurates. These components are largely known in the art, seee.g. U.S. Pat. No. 4,579,906 (e.g. col. 3, lines 30–41), U.S. Pat. No.5,393,812; see also Plastics Additives Handbook, Ed. by H. Zweifel,5^(th) Ed., Hanser Publ., Munich 2001, pp. 681–698.

The phosphazene flame retardants are well known in the art. They aredisclosed for example in EP1104766, JP07292233, DE19828541, DE1988536,JP11263885, U.S. Pat. Nos. 4,107,108, 4,108,805 and 4,079,035 and6,265,599. The relevant disclosures of the U.S. Patents are herebyincorporated by reference.

PTFE, polytetrafluoroethylene (for example Teflon® 6C; E. I. Du Pont),may be advantageously added to the present compositions as an additionalflame retardant, as disclosed in U.S. application Ser. No. 60/312,517,filed Aug. 15, 2001.

Component (b) is advantageously contained in the composition of theinvention in an amount from about 0.5% to about 45% by weight of thepolymer substrate (a); for instance about 3% to about 40%; for exampleabout 5% to about 35% by weight of component (a). For example, component(b) is employed from about 0.5% to about.15% by weight, from about 1% toabout 15%, from about 3% to about 15% or from about 5% to about 15% byweight, based on the weight of the polymer substrate. For example,component (b) is employed from about 8% to about 20% or from about 9% toabout 20% by weight, based on the weight of the polymer substrate. Forexample, component (b) is present from about 15% to about 20% by weight,based on the weight of the polymer substrate. For example, component (b)is present at about 15%, 16%, 17%, 18%, 19% or about 20%, based on theweight of the polymer substrate. For example, component (b) is employedfrom about 0.5% to about 12%, from about 0.5% to about 10%, from about0.5% to about 8%, or from about 0.5% to about 6% by weight, based on theweight of the polymer substrate.

The ratio (parts by weight) of component (i) to component (ii) is forexample between about 100:1 to about 1:100, for instance from about 50:1to about 1:50, or about 10:1 to about 1:10, or about 5:1 to about 1:5.For example the ratio of component (i) to component (ii) is from about100:1 to about 1:50, from about 100:1 to about 1:10, or from about 100:1to about 1:5. For example, the weight ratio of component (i) tocomponent (ii) is from about 1:100 to about 50:1, from about 1:100 toabout 10:1, or from about 1:100 to about 5:1. For example, the weightratio of component (i) to component (ii) is about 1:4, 1:3, 1:2, 1:1,2:1, 3:1 or 4:1. For example, the weight ratio of component (i) tocomponent (ii) is from about 1:1 to about 1:2.

The amount of component (ii) used also depends on the effectiveness ofthe specific compound(s), the polymer and the specific application type.

Sterically Hindered Amine Stabilizers

The present hindered amines are for example monomeric compounds or areoligomeric or polymeric compounds.

Hindered alkoxyamine stabilizers are well known in the art, also knownas N-alkoxy hindered amines and NOR hindered amines or NOR hinderedamine light stabilizers or NOR HALS.

They are disclosed for example in U.S. Pat. Nos. 5,004,770, 5,204,473,5,096,950, 5,300,544, 5,112,890, 5,124,378, 5,145,893, 5,216,156,5,844,026, 6,117,995, 6,271,377, 6,392,041, 6,376,584 and 6,472,456 andU.S. application Ser. Nos. 09/714,717, filed Nov. 16, 2000, and60/312,517, filed Aug. 15, 2001. The relevant disclosures of thesepatents and applications are hereby incorporated by reference.

U.S. Pat. Nos. 6,271,377, 6,392,041 and 6,376,584 cited above disclosehindered hydroxyalkoxyamine stabilizers. For the purposes of thisinvention, the hindered hydoxyalkoxyamine stabilizers are considered asubset of the hindered alkoxyamine stabilizers. Hinderedhydroxyalkoxyamine stabilizers are also known as N-hydroxyalkoxyhindered amines, or NORol HALS.

Suitable hindered amines according to the present invention include forexample:

-   -   NOR1        1-cyclohexyloxy-2,2,6,6-tetramethyl4-octadecylaminopiperidine;    -   NOR2 bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate;    -   NOR3        2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-(2-hydroxyethylamino-s-triazine;    -   NOR4        2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-chloro-s-triazine;    -   NOR5        1-(2-hydroxy-2-methylpropoxy)-4-hydroxy-2,2,6,6-tetramethylpiperidine;    -   NOR6        1-(2-hydroxy-2-methylpropoxy)-4-oxo-2,2,6,6-tetramethylpiperidine;    -   NOR7        1-(2-hydroxy-2-methylpropoxy)-4-octadecanoyloxy-2,2,6,6-tetramethylpiperidine;    -   NOR8        bis(1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl)sebacate;    -   NOR9        bis(1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl)adipate;    -   NOR10        2,4-bis{N-[1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl]-N-butylamino}6-(2-hydroxyethylamino)-s-triazine;    -   NOR11 the reaction product of        2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-chloro-s-triazine        with N,N′-bis(3-aminopropyl)ethylenediamine) [CAS Reg. No.        191680-81-6];

in which n is from 1 to 15; and

-   -   NOR13        bis(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)adipate.

Compound NOR12 is disclosed in example 2 of U.S. Pat. No. 6,117,995.

The optional hindered amine stabilizers are advantageously contained inthe composition of the invention in an amount from about 0.05% to about20% by weight based on the polymer substrate (a); for example from about0.1% to about 10% by weight; for example from about 0.2% to about 8% byweight; for instance from about 0.5% to about 3% by weight. For example,the stabilizers of component (i) are present from about 0.05% to about15%, from about 0.05% to about 10%, from about 0.05% to about 8%, fromabout 0.05% to about 5% or from about 0.05% to about 3% by weight basedon the weight of substrate (a). For example, the stabilizers ofcomponent (i) are present from about 0.1% to about 20%, from about 0.2to about 20%, from about 0.5 to about 20% or from about 1% to about 20%by weight based on the weight of substrate (a).

The compositions of the present invention are useful for manyapplications, for example outdoor applications, including the following:

-   Thermoplastic olefins-   Paintable thermoplastic olefins-   Polypropylene molded articles-   Polyethylene film-   Thermoplastic elastomers with other costabilizers-   Grease-filled wire and cable insulation-   Coatings-   Coatings over plastic substrates-   Polyolefin tanks or containers containing chemicals-   Polyolefin films with an antifog agent-   Polyolefin films with IR thermal fillers such as hydrotalcites, e.g.    DHT4A-   Polyolefin films with an antistatic agent-   Flame-resistant molded polypropylene articles-   Flame-resistant molded thermoplastic olefins-   Flame-resistant polyethylene film-   Pre-formed films for lamination to plastic substrates-   Electronic appliances-   Containers, boxes, bins for storage and transportation-   Automotive applications e.g. dashboard, back board-   Furniture e.g. stadium seats, public seats-   Roofing sheets-   Roofing membranes-   Flooring materials-   Liners-   Profiles, for example window and door profiles-   Geomembranes-   Awning fabrics-   Banner films-   Upholstery-   Drapery-   Carpeting-   Tents, tarpaulins-   Surgical gowns, caps and other hospital applications-   Fabrics-   Ropes-   Nets-   Tire cords-   Parachutes-   Thermoplastic electrical parts (plugs, sockets or wire insulations)

The compositions of the present invention are useful in textilelaminates and as coatings of substrates as described in U.S. Pat. Nos.6,235,658 and 6,251,995, the relevant disclosures of which are herebyincorporated by reference.

The materials containing the stabilizers described herein can be usedfor the production of moldings, rotomolded articles, injection moldedarticles, blow molded articles, mono- and multilayer films, extrudedprofiles, surface coatings and the like.

The compositions of the invention may optionally also contain variousconventional additives, for example in amounts from about 0.01 to about10%, for instance from about 0.025 to about 4%, for example from about0.1 to about 2% by weight of component (a), such as the materials listedbelow, or mixtures thereof.

1. Antioxidants

1.1. Alkylated monophenols, for example 2,6-di-tert-butyl4-methylphenol,2-tert-butyl4,6-dimethylphenol, 2,6-di-tert-butyl-4-ethylphenol,2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-tert-butyl-4-isobutylphenol,2,6-dicyclopentyl-4-methylphenol,2-(α-methylcyclohexyl)-4,6-dimethylphenol,2,6-dioctadecyl-4-methylphenol, 2,4,6-tricyclohexylphenol,2,6-di-tert-butyl-4-methoxymethylphenol, nonylphenols which are linearor branched in the side chains, for example,2,6-di-nonyl-4-methylphenol,2,4-dimethyl-6-(1′-methylundec-1′-yl)phenol,2,4-dimethyl-6-(1′-methylheptadec-1′-yl)phenol,2,4-dimethyl-6-(1′-methyltridec-1′-yl)phenol and mixtures thereof.

1.2. Alkylthiomethylphenols, for example2,4-dioctylthiomethyl-6-tert-butylphenol,2,4-dioctylthiomethyl-6-methylphenol,2,4-dioctylthiomethyl-6-ethylphenol,2,6-di-dodecylthiomethyl-4-nonylphenol.

1.3. Hydroquinones and alkylated hydroquinones, for example2,6-di-tert-butyl-4-methoxyphenol, 2,5-di-tert-butylhydroquinone,2,5-di-tert-amylhydroquinone, 2,6-diphenyl-4-octade-cyloxyphenol,2,6-di-tert-butylhydroquinone, 2,5-di-tert-butyl-4-hydroxyanisole,3,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyphenylstearate, bis-(3,5-di-tert-butyl-4-hydroxyphenyl)adipate.

1.4. Tocopherols, for example α-tocopherol, β-tocopherol, γ-tocopherol,δ-tocopherol and mixtures thereof (Vitamin E).

1.5. Hydroxylated thiodiphenyl ethers, for example2,2′-thiobis(6-tert-butyl4-methylphenol), 2,2′-thiobis(4-octylphenol),4,4′-thiobis(6-tert-butyl-3-methylphenol),4,4′-thiobis(6-tert-butyl-2-methylphenol),4,4′-thiobis-(3,6-di-sec-amylphenol),4,4′-bis(2,6-dimethyl4-hydroxyphenyl)disulfide.

1.6. Alkylidenebisphenols, for example2,2′-methylenebis(6-tert-butyl-4-methylphenol),2,2′-methylenebis(6-tert-butyl-4-ethylphenol),2,2′-methylenebis[4-methyl-6-(α-methylcyclohexyl)-phenol],2,2′-methylenebis(4-methyl-6-cyclohexylphenol),2,2′-methylenebis(6-nonyl-4-methylphenol),2,2′-methylenebis(4,6-di-tert-butylphenol),2,2′-ethylidenebis(4,6-di-tert-butylphenol),2,2′-ethylidenebis(6-tert-butyl4-isobutylphenol),2,2′-methylenebis[6-(α-methylbenzyl)-4-nonylphenol],2,2′-methylenebis[6-(α,α-dimethylbenzyl)-4-nonylphenol],4,4′-methylenebis(2,6-di-tert-butylphenol),4,4′-methylenebis(6-tert-butyl-2-methylphenol),1,1-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)butane,2,6-bis(3-tert-butyl-5-methyl-2-hydroxybenzyl)-4-methylphenol,1,1,3-tris(5-tert-butyl4-hydroxy-2-methylphenyl)butane,1,1-bis(5-tert-butyl-4-hydroxy-2-methyl-phenyl)-3-n-dodecylmercaptobutane,ethylene glycol bis[3,3-bis(3′-tert-butyl4′-hydroxyphenyl)butyrate],bis(3-tert-butyl-4-hydroxy-5-methyl-phenyl)dicyclopentadiene,bis[2-(3′-tert-butyl-2′-hydroxy-5′-methylbenzyl)-6-tert-butyl-4-methylphenyl]terephthalate,1,1-bis-(3,5-dimethyl-2-hydroxyphenyl)butane,2,2-bis-(3,5-di-tert-butyl-4-hydroxyphenyl)propane,2,2-bis-(5-tert-butyl-4-hydroxy2-methylphenyl)-4-n-dodecylmercaptobutane,1,1,5,5-tetra-(5-tert-butyl-4-hydroxy-2-methylphenyl)pentane.

1.7: O—, N— and S-benzyl compounds, for example3,5,3′,5′-tetra-tert-butyl-4,4′-dihydroxydibenzyl ether,octadecyl-4-hydroxy-3,5-dimethylbenzylmercaptoacetate,tridecyl-4-hydroxy-3,5-di-tert-butylbenzylmercaptoacetate,tris(3,5-di-tert-butyl-4-hydroxybenzyl)amine,bis(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)dithioterephthalate,bis(3,5-di-tert-butyl-4-hydroxybenzyl)sulfide,isooctyl-3,5-di-tert-butyl-4-hydroxybenzylmercaptoacetate.

1.8. Hydroxybenzylated malonates, for exampledioctadecyl-2,2-bis-(3,5-di-tert-butyl-2-hydroxybenzyl)-malonate,di-octadecyl-2-(3-tert-butyl-4-hydroxy-5-methylbenzyl)-malonate,di-dodecylmeraptoethyl-2,2-bis-(3,5-di-tert-butyl-4-hydroxybenzyl)malonate,bis[4-(1,1,3,3-tetramethylbutyl)phenyl]-2,2-bis(3,5-di-tert-butyl-4-hydroxybenzyl)malonate.

1.9. Aromatic hydroxybenzyl compounds, for example1,3,5-tris-(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene,1,4-bis(3,5-di-tert-butyl-4-hydroxybenzyl)-2,3,5,6-tetramethylbenzene,2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)phenol.

1.10. Triazine Compounds, for example2,4-bis(octylmercapto)-6-(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-triazine,2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-triazine,2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,3,5-triazine,2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,2,3-triazine,1,3,5-tris-(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate,1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate,2,4,6-tris-(3,5-di-tert-butyl-4-hydroxyphenylethyl)-1,3,5-triazine,1,3,5-tris(3,5-di-tert-butyl-4-hydroxy-phenylpropionyl)-hexahydro-1,3,5-triazine,1,3,5-tris(3,5-dicyclohexyl4-hydroxybenzyl)isocyanurate.

1.11. Benzylphosphonates, for exampledimethyl-2,5-di-tert-butyl-4-hydroxybenzylphosphonate,diethyl-3,5-di-tert-butyl-4-hydroxybenzylphosphonate,dioctadecyl3,5-di-tert-butyl-4-hydroxybenzylphosphonate,dioctadecyl-5-tert-butyl-4-hydroxy-3-methylbenzylphosphonate, thecalcium salt of the monoethyl ester of3,5-di-tert-butyl-4-hydroxybenzylphosphonic acid.

1.12. Acylaminophenols, for example 4-hydroxylauranilide,4-hydroxystearanilide, octylN-(3,5-di-tert-butyl-4-hydroxyphenyl)carbamate.

1.13. Esters of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid withmono- or polyhydric alcohols, e.g. with methanol, ethanol, n-octanol,i-octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol,1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethyleneglycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxamide, 3-thiaundecanol,3-thiapentadecanol, trimethylhexanediol, trimethylolpropane,4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.14. Esters of β-(5-tert-butyl-4-hydroxy-3-methylphenyl)propionic acidwith mono- or polyhydric alcohols, e.g. with methanol, ethanol,n-octanol, i-octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol,ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethyleneglycol, diethylene glycol, triethylene glycol, pentaerythritol,tris(hydroxyethyl) isocyanurate, N,N′-bis-(hydroxyethyl)oxamide,3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol,trimethylolpropane,4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.15. Esters of β-(3,5-dicyclohexyl-4-hydroxyphenyl)propionic acid withmono- or polyhydric alcohols, e.g. with methanol, ethanol, octanol,octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol,1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethyleneglycol, triethylene glycol, pentaerythritol,tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxamide,3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol,trimethylolpropane,4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.16. Esters of 3,5-di-tert-butyl-4-hydroxyphenyl acetic acid with mono-or polyhydric alcohols, e.g. with methanol, ethanol, octanol,octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol,1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethyleneglycol, triethylene glycol, pentaerythritol,tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxamide,3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol,trimethylolpropane,4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.17. Amides of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid e.g.N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hexamethylenediamide,N,N′-bis(3,5-di-tert-butyl-4-hydroxy-phenylpropionyl)trimethylenediamide,N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)-hydrazide,N,N′-bis[2-(3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyloxy)ethyl]oxamide (Naugard®XL-1 supplied by Uniroyal).

1.18. Ascorbic acid (vitamin C)

1.19. Aminic antioxidants, for exampleN,N′-di-isopropyl-p-phenylenediamine,N,N′-di-sec-butyl-p-phenylenediamine,N,N′-bis(1,4-dimethylpentyl)-p-phenylenediamine,N,N′-bis(1-ethyl-3-methylpentyl)-p-phenylenediamine,N,N′-bis(1-methylheptyl)-p-phenylenediamine,N,N′-dicyclohexyl-p-phenylenediamine, N,N′-diphenyl-p-phenylenediamine,N,N′-bis(2-naphthyl)-p-phenylenediamine,N-isopropyl-N′-phenyl-p-phenylenediamine,N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine,N-(1-methylheptyl)-N′-phenyl-p-phenylenediamine,N-cyclohexyl-N′-phenyl-p-phenylenediamine,4-(p-toluenesulfamoyl)diphenylamine,N,N′-dimethyl-N,N′-di-sec-butyl-p-phenylenediamine, diphenylamine,N-allyldiphenylamine, 4-isopropoxydiphenylamine,N-phenyl-1-naphthylamine, N-(4-tert-octylphenyl)-1-naphthylamine,N-phenyl-2-naphthylamine, octylated diphenylamine, for examplep,p′-di-tert-octyldiphenylamine, 4-n-butylaminophenol,4-butyrylaminophenol, 4-nonanoylaminophenol, 4-dodecanoylaminophenol,4-octa-decanoylaminophenol, bis(4-methoxyphenyl)amine,2,6-di-tert-butyl-4-dimethylaminomethyl-phenol,2,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane,N,N,N′,N′-tetramethyl-4,4′-diaminodiphenylmethane,1,2-bis[(2-methylphenyl)amino]ethane, 1,2-bis(phenylamino)propane,(o-tolyl)biguanide, bis[4-( 1′,3′-dimethylbutyl)phenyl]amine,tert-octylated N-phenyl-1-naphthylamine, a mixture of mono- anddialkylated tert-butyl/tert-octyldiphenylamines, a mixture of mono- anddialkylated nonyldiphenylamines, a mixture of mono- and dialkylateddodecyldiphenylamines, a mixture of mono- and dialkylatedisopropyl/isohexyldiphenylamines, a mixture of mono- und dialkylatedtert-butyidiphenylamines, 2,3-dihydro-3,3-dimethyl4H-1,4-benzothiazine,phenothiazine, a mixture of mono- und dialkylatedtert-butyl/tert-octylphenothiazines, a mixture of mono- und dialkylatedtert-octyl-phenothiazines, N-allylphenothiazin,N,N,N′,N′-tetraphenyl-1,4-diaminobut-2-ene,N,N-bis(2,2,6,6-tetramethyl-piperid-4-yl-hexamethylenediamine,bis(2,2,6,6-tetramethylpiperid-4-yl)sebacate,2,2,6,6-tetramethylpiperidin-4-one, 2,2,6,6-tetramethylpiperidin-4-ol.

2. UV absorbers and light stabilizers

2.1. 2-(2-Hydroxyphenyl)-2H-benzotriazoles, for example known commercialhydroxyphenyl-2H-benzotriazoles and benzotriazoles as disclosed in, U.S.Pat. Nos. 3,004,896; 3,055,896; 3,072,585; 3,074,910; 3,189,615;3,218,332; 3,230,194; 4,127,586; 4,226,763; 4,275,004; 4,278,589;4,315,848; 4,347,180; 4,383,863; 4,675,352; 4,681,905, 4,853,471;5,268,450; 5,278,314; 5,280,124; 5,319,091; 5,410,071; 5,436,349;5,516,914; 5,554,760; 5,563,242; 5,574,166; 5,607,987, 5,977,219 and6,166,218 such as 2-(2-hydroxy-5-methylphenyl)-2H-benzotriazole,2-(3,5-di-t-butyl-2-hydroxyphenyl)-2H-benzotriazole,2-(2-hydroxy-5-t-butylphenyl)-2H-benzotriazole,2-(2-hydroxy-5-t-octylphenyl)-2H-benzotriazole,5-chloro-2-(3,5-di-t-butyl-2-hydroxyphenyl)-2H-benzotriazole,5-chloro-2-(3-t-butyl-2-hydroxy-5-methylphenyl)-2H-benzotriazole,2-(3-sec-butyl-5-t-butyl-2-hydroxyphenyl)-2H-benzotriazole,2-(2-hydroxy-4-octyloxyphenyl)-2H-benzotriazole,2-(3,5-di-t-amyl-2-hydroxyphenyl)-2H-benzotriazole,2-(3,5-bis-α-cumyl-2-hydroxyphenyl)-2H-benzotriazole,2-(3-t-butyl-2-hydroxy-5-(2-(ω-hydroxy-octa-(ethyleneoxy)carbonyl-ethyl)-,phenyl)-2H-benzotriazole,2-(3-dodecyl-2-hydroxy-5-methylphenyl)-2H-benzotriazole,2-(3-t-butyl-2-hydroxy-5-(2-octyloxycarbonyl)ethylphenyl)-2H-benzotriazole,dodecylated 2-(2-hydroxy-5-methylphenyl)-2H-benzotriazole,2-(3-t-butyl-2-hydroxy-5-(2-octyloxycarbonylethyl)phenyl)-5-chloro-2H-benzotriazole,2-(3-tert-butyl-5-(2-(2-ethylhexyloxy)-carbonylethyl)-2-hydroxyphenyl)-5-chloro-2H-benzotriazole,2-(3-t-butyl-2-hydroxy-5-(2-methoxycarbonylethyl)phenyl)-5-chloro-2H-benzotriazole,2-(3-t-butyl-2-hydroxy-5-(2-methoxycarbonylethyl)phenyl)-2H-benzotriazole,2-(3-t-butyl-5-(2-(2-ethylhexyloxy)carbonylethyl)-2-hydroxyphenyl)-2H-benzotriazole,2-(3-t-butyl-2-hydroxy-5-(2-isooctyloxycarbonylethyl)phenyl-2H-benzotriazole,2,2′-methylene-bis(4-t-octyl-(6-2H-benzotriazol-2-yl)phenol),2-(2-hydroxy-3-α-cumyl-5-t-octylphenyl)-2H-benzotriazole,2-(2-hydroxy-3-t-octyl-5-α-cumylphenyl)-2H-benzotriazole,5-fluoro-2-(2-hydroxy-3,5-di-α-cumylpheny)-2H-benzotriazole,5-chloro-2-(2-hydroxy-3,5-di--cumylphenyl)-2H-benzotriazole,5-chloro-2-(2-hydroxy-3-α-cumyl-5-t-octylphenyl)-2H-benzotriazole,2-(3-t-butyl-2-hydroxy-5-(2-isooctyloxycarbonylethyl)phenyl)-5-chloro-2H-benzotriazole,5-trifluoromethyl-2-(2-hydroxy-3-α-cumyl-5-t-octylphenyl)-2H-benzotriazole,5-trifluoromethyl-2-(2-hydroxy-5-t-octylphenyl)-2H-benzotri5-trifluoromethyl-2-(2-hydroxy-3,5-di-t-octylphenyl)-2H-benzotriazole,methyl3-(5-trifluoromethyl-2H-benzotriazol-2-yl)-5-t-butyl4-hydroxyhydrocinnamate,5-butylsulfonyl-2-(2-hydroxy-3-α-cumyl-5-t-octylphenyl)-2H-benzotriazole,5-trifluoromethyl-2-(2-hydroxy-3-α-cumyl-5-t-butylphenyl)-2H-benzotriazole,5-trifluoromethyl-2-(2-hydroxy-3,5-di-t-butylphenyl)-2H-benzotriazole,5-trifluoromethyl-2-(2-hydroxy-3,5-di-α-cumylphenyl)-2H-benzotriazole,5-butylsulfonyl-2-(2-hydroxy-3,5-di-t-butylphenyl)-2H-benzotriazole and5-phenylsulfonyl-2-(2-hydroxy-3,5-di-t-butylphenyl)-2H-benzotriazole.

2.2. 2-Hydroxybenzophenones, for example the 4-hydroxy, 4-methoxy,4-octyloxy, 4-decyloxy, 4-dodecyloxy, 4-benzyloxy, 4,2′,4′-trihydroxyand 2′-hydroxy4,4′-dimethoxy derivatives.

2.3. Esters of substituted and unsubstituted benzoic acids, as forexample 4-tertbutyl-phenyl salicylate, phenyl salicylate, octylphenylsalicylate, dibenzoyl resorcinol, bis(4-tert-butylbenzoyl) resorcinol,benzoyl resorcinol, 2,4-di-tert-butylphenyl3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl3,5-di-tert-butyl-4-hydroxybenzoate, 2-methyl-4,6-di-tert-butylphenyl3,5-di-tert-butyl-4-hydroxybenzoate.

2.4. Acrylates, for example ethyl α-cyano-β,β-diphenylacrylate, isooctylα-cyano-β,β-diphenylacrylate, methyl α-carbomethoxycinnamate, methylα-cyano-β-methyl-p-methoxy-cinnamate, butylα-cyano-β-methyl-p-methoxy-cinnamate, methylα-carbomethoxy-p-methoxycinnamate andN-(β-carbomethoxy-β-cyanovinyl)-2-methylindoline.

2.5. Nickel compounds, for example nickel complexes of2,2′-thio-bis-[4-(1,1,3,3-tetramethyl-butyl)phenol], such as the 1:1 or1:2 complex, with or without additional ligands such as n-butylamine,triethanolamine or N-cyclohexyldiethanolamine, nickeldibutyldithiocarbamate, nickel salts of the monoalkyl esters, e.g. themethyl or ethyl ester, of 4-hydroxy-3,5-di-tert-butylbenzylphosphonicacid, nickel complexes of ketoximes, e.g. of 2-hydroxy4-methylphenylundecylketoxime, nickel complexes of1-phenyl-4-lauroyl-5-hydroxypyrazole, with or without additionalligands.

2.6. Sterically hindered amines, for examplebis(2,2,6,6-tetramethyl-4-piperidyl)sebacate,bis(2,2,6,6-tetramethyl4-piperidyl)succinate,bis(1,2,2,6,6-pentamethyl4-piperidyl)sebacate,bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate,bis(1,2,2,6,6-pentamethyl-4-piperidyl)n-butyl-3,5-di-tert-butyl-4-hydroxybenzylmalonate,the condensate of1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinicacid, linear or cyclic condensates ofN,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and4-tert-octylamino-2,6-dichloro-1,3,5-triazine,tris(2,2,6,6-tetramethyl4-piperidyl)nitrilotriacetate,tetrakis(2,2,6,6-tetramethyl4-piperidyl)-1,2,3,4-butane-tetracarboxylate,1,1′-(1,2-ethanediyl)-bis(3,3,5,5-tetramethylpiperazinone),4-benzoyl-2,2,6,6-tetramethylpiperidine,4-stearyloxy-2,2,6,6-tetramethyl-piperidine,bis(1,2,2,6,6-pentamethylpiperidyl)-2-n-butyl-2-(2-hydroxy-3,5-di-tert-butylbenzyl)-malonate,3-n-octyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decan-2,4-dione,bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl)sebacate,bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl)succinate, linear or cycliccondensates ofN,N′-bis-(2,2,6,6-tetramethyl4-piperidyl)hexamethylenediamine and4-morpholino-2,6-dichloro-1,3,5-triazine, the condensate of2-chloro4,6-bis(4-n-butylamino-2,2,6,6-tetramethylpiperidyl)-1,3,5-triazineand 1,2-bis(3-aminopropylamino)ethane, the condensate of2-chloro4,6-di-(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-triazineand 1,2-bis-(3-aminopropylamino)ethane,8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione,3-dodecyl-1-(2,2,6,6-tetramethyl4-piperidyl)pyrrolidin-2,5-dione,3-dodecyl-1-(1,2,2,6,6-pentamethyl-4-piperidyl)pyrrolidine-2,5-dione, amixture of 4-hexadecyloxy- and4-stearyloxy-2,2,6,6-tetramethylpiperidine, a condensation product ofN,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and4-cyclohexylamino-2,6-dichloro-1,3,5-triazine, a condensation product of1,2-bis(3-aminopropylamino)ethane and 2,4,6-trichloro-1,3,5-triazine aswell as 4-butylamino-2,2,6,6-tetramethylpiperidine (CAS Reg. No.[136504-96-6]); N-(2,2,6,6-tetramethyl4-piperidyl)-n-dodecylsuccinimid,N-(1,2,2,6,6-pentamethyl-4-piperidyl)-n-dodecylsuccinimid,2-undecyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4-oxo-spiro[4,5]decane, areaction product of7,7,9,9-tetramethyl-2-cycloundecyl-1-oxa-3,8-diaza-4-oxospiro[4,5]decaneund epichlorohydrin,1,1-bis(1,2,2,6,6-pentamethyl-4-piperidyloxycarbonyl)-2-(4-methoxyphenyl)ethene,N,N′-bis-formyl-N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine,diester of 4-methoxy-methylene-malonic acid with1,2,2,6,6-pentamethyl-4-hydroxypiperidine,poly[methylpropyl-3-oxy4-(2,2,6,6-tetramethyl-4-piperidyl)]siloxane,reaction product of maleic acid anhydride-α-olefin-copolymer with2,2,6,6-tetramethyl-4-aminopiperidine or1,2,2,6,6-pentamethyl-4-aminopiperidine.

2.7. Oxamides, for example 4,4′-dioctyloxyoxanilide,2,2′-diethoxyoxanilide, 2,2′-dioctyloxy-5,5′-di-tert-butoxanilide,2,2′-didodecyloxy-5,5′-di-tert-butoxanilide, 2-ethoxy-2′-ethyloxanilide,N,N′-bis(3-dimethylaminopropyl)oxamide,2-ethoxy-5-tert-butyl-2′-ethoxanilide and its mixture with2-ethoxy-2′-ethyl-5,4′-di-tert-butoxanilide, mixtures of o- andp-methoxy-disubstituted oxanilides and mixtures of o- andp-ethoxy-disubstituted oxanilides.

2.8. Tris-aryl-o-hydroxyphenyl-s-triazines, for example known commercialtris-aryl-o-hydroxyphenyl-s-triazines and triazines as disclosed in, WO96/28431 and U.S. Pat. Nos. 3,843,371; 4,619,956; 4,740,542; 5,096,489;5,106,891; 5,298,067; 5,300,414; 5,354,794; 5,461,151; 5,476,937;5,489,503; 5,543,518; 5,556,973; 5,597,854; 5,681,955; 5,726,309;5,736,597; 5,942,626; 5,959,008; 5,998,116; 6,013,704; 6,060,543;6,187,919; 6,242,598 and 6,255,483, for example4,6-bis-(2,4-dimethylphenyl)-2-(2-hydroxy-4-octyloxyphenyl)-s-triazine,Cyasorb® 1164, Cytec Corp,4,6-bis-(2,4-dimethylphenyl)-2-(2,4-dihydroxyphenyl)-s-triazine,2,4-bis(2,4-dihydroxyphenyl)-6-(4-chlorophenyl)-s-triazine,2,4-bis[2-hydroxy-4-(2-hydroxyethoxy)phenyl]-6-(4-chlorophenyl)-s-triazine,2,4-bis[2-hydroxy-4-(2-hydroxy-4-(2-hydroxyethoxy)phenyl]-6-(2,4-dimethylphenyl)-s-triazine,2,4-bis[2-hydroxy4-(2-hydroxyethoxy)phenyl]-6-(4-bromophenyl)-s-triazine,2,4-bis[2-hydroxy4-(2-acetoxyethoxy)-phenyl]-6-(4-chlorophenyl)-s-triazine,2,4-bis(2,4-dihydroxyphenyl)-6-(2,4-dimethylphenyl)-s-triazine,2,4-bis(4-biphenylyl)-6-(2-hydroxy-4-octyloxycarbonylethylideneoxyphenyl)-s-triazine,2-phenyl-4-[2-hydroxy4-(3-sec-butyloxy-2-hydroxypropyloxy)phenyl]-6-[2-hydroxy4-(3-sec-amyloxy-2-hydroxypropyloxy)phenyl]-s-triazine,2,4-bis(2,4-dimethylphenyl)-6-[2-hydroxy-4-(3-benzyloxy-2-hydroxypropyloxy)phenyl]-s-triazine,2,4-bis(2-hydroxy4-n-butyloxyphenyl)-6-(2,4-di-n-butyloxyphenyl)-s-triazine,2,4-bis(2,4-dimethylphenyl)-6-[2-hydroxy-4-(3-nonyloxy*-2-hydroxypropyloxy)-5-α-cumylphenyl]-s-triazine(* denotes a mixture of octyloxy, nonyloxy and decyloxy groups),methylenebis-{2,4-bis(2,4-dimethylphenyl)-6-[2-hydroxy-4-(3-butyloxy-2-hydroxypropoxy)phenyl]-s-triazine},methylene bridged dimer mixture bridged in the 3:5′, 5:5′ and 3:3′positions in a 5:4:1 ratio,2,4,6-tris(2-hydroxy-4-isooctyloxycarbonylisopropylideneoxy-phenyl)-s-triazine,2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-hexyloxy-5-α-cumylphenyl)-s-triazine,2-(2,4,6-trimethylphenyl)-4,6-bis[2-hydroxy-4-(3-butyloxy-2-hydroxypropyloxy)phenyl]-s-triazine,2,4,6-tris[2-hydroxy-4-(3-sec-butyloxy-2-hydroxypropyloxy)phenyl]-s-triazine,mixture of4,6-bis-(2,4-dimethylphenyl)-2-(2-hydroxy-4-(3-dodecyloxy-2-hydroxypropoxy)-phenyl)-s-triazineand4,6-bis-(2,4-dimethylphenyl)-2-(2-hydroxy-4-(3-tridecyloxy-2-hydroxypropoxy)-phenyl)-s-triazine,Tinuvin® 400, Ciba Specialty Chemicals Corp.,4,6-bis-(2,4-dimethylphenyl)-2-(2-hydroxy-4-(3-(2-ethylhexyloxy)-2-hydroxypropoxy)-phenyl)-s-triazineand 4,6-diphenyl-2-(4-hexyloxy-2-hydroxyphenyl)-s-triazine.

3. Metal deactivators, for example N,N′-diphenyloxamide,N-salicylal-N′-salicyloyl hydrazine, N,N′-bis(salicyloyl) hydrazine,N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl) hydrazine,3-salicyloylamino-1,2,4-triazole, bis(benzylidene)oxalyl dihydrazide,oxanilide, isophthaloyl dihydrazide, sebacoyl bisphenylhydrazide,N,N′-diacetyladipoyl dihydrazide, N,N′-bis(salicyloyl)oxalyldihydrazide, N,N′-bis(salicyloyl)thiopropionyl dihydrazide.

4. Phosphites and phosphonites, for example triphenyl phosphite,diphenyl alkyl phosphites, phenyl dialkyl phosphites, tris(nonylphenyl)phosphite, trilauryl phosphite, trioctadecyl phosphite, distearylpentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite,diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite,bis(2,6-di-tert-butyl-4-methylphenyl)-pentaerythritol diphosphite,diisodecyloxypentaerythritol diphosphite,bis(2,4-di-tert-butyl-6-methylphenyl)pentaerythritol diphosphite,bis(2,4,6-tris(tert-butyl-phenyl)pentaerythritol diphosphite, tristearylsorbitol triphosphite, tetrakis(2,4-di-tert-butylphenyl)4,4′-biphenylene diphosphonite,6-isooctyloxy-2,4,8,10-tetra-tert-butyl-12H-dibenz[d,g]-1,3,2-dioxaphosphocin,bis(2,4-di-tert-butyl-6-methylphenyl)methyl phosphite,bis(2,4-di-tert-butyl-6-methylphenyl)ethyl phosphite,6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyl-dibenz[d,g]-1,3,2-dioxaphosphocin,2,2′,2″-nitrilo[triethyltris(3,3′,5,5′-tetra-tert-butyl-1,1′-biphenyl-2,2′-diyl)phosphite],2-ethylhexyl(3,3′,5,5′-tetra-tert-butyl-1,1′-biphenyl-2,2′-diyl)phosphite,5-butyl-5-ethyl-2-(2,4,6-tri-tert-butylphenoxy)-1,3,2-dioxaphosphirane.

Specific examples are the following phosphites:

Tris(2,4-di-tert-butylphenyl)phosphite (Irgafos® 168, Ciba-Geigy),tris(nonylphenyl)phosphite,

5. Hydroxylamines, for example, N,N-dibenzylhydroxylamine,N,N-diethylhydroxylamine, N,N-dioctylhydroxylamine,N,N-dilaurylhydroxylamine, N,N-ditetradecylhydroxylamine,N,N-dihexadecylhydroxylamine, N,N-dioctadecylhydroxylamine,N-hexadecyl-N-octadecylhydroxylamine,N-heptadecyl-N-octadecylhydroxylamine, N,N-dialkylhydroxylamine derivedfrom hydrogenated tallow amine.

6. Nitrones, for example, N-benzyl-alpha-phenyl-nitrone,N-ethyl-alpha-methyl-nitrone, N-octyl-alpha-heptyl-nitrone,N-lauryl-alpha-undecyl-nitrone, N-tetradecyl-alpha-tridcyl-nitrone,N-hexadecyl-alpha-pentadecyl-nitrone,N-octadecyl-alpha-heptadecyl-nitrone,N-hexadecyl-alpha-heptadecyl-nitrone,N-ocatadecyl-alpha-pentadecyl-nitrone,N-heptadecyl-alpha-heptadecyl-nitrone,N-octadecyl-alpha-hexadecyl-nitrone, nitrone derived fromN,N-dialkylhydroxylamine derived from hydrogenated tallow amine.

7. Thiosynergists, for example, dilauryl thiodipropionate or distearylthiodipropionate.

8. Peroxide scavengers, for example esters of β-thiodipropionic acid,for example the lauryl, stearyl, myristyl or tridecyl esters,mercaptobenzimidazole or the zinc salt of 2-mercapto-benzimidazole, zincdibutyldithiocarbamate, dioctadecyl disulfide, pentaerythritoltetrakis(β-dodecylmercapto)propionate.

9. Polyamide stabilizers, for example, copper salts in combination withiodides and/or phosphorus compounds and salts of divalent manganese.

10. Basic co-stabilizers, for example, melamine, polyvinylpyrrolidone,dicyandiamide, triallyl cyanurate, urea derivatives, hydrazinederivatives, amines, polyamides, polyurethanes, alkali metal salts andalkaline earth metal salts of higher fatty acids for example calciumstearate, zinc stearate, magnesium behenate, magnesium stearate, sodiumricinoleate and potassium palmitate, antimony pyrocatecholate or zinkpyrocatecholate.

11. Nucleating agents, for example, inorganic substances such as talcum,metal oxides such as titanium dioxide or magnesium oxide, phosphates,carbonates or sulfates of, for example, alkaline earth metals; organiccompounds such as mono- or polycarboxylic acids and the salts thereof,e.g. 4-tert-butylbenzoic acid, adipic acid, diphenylacetic acid, sodiumsuccinate or sodium benzoate; polymeric compounds such as ioniccopolymers (ionomers). Specific examples are1,3:2,4-bis(3′,4′-dimethylbenzylidene)sorbitol,1,3:2,4-di(paramethyldibenzylidene)sorbitol, und1,3:2,4-di(benzylidene)sorbitol.

12. Fillers and reinforcing agents, for example, calcium carbonate,silicates, glass fibres, glass bulbs, asbestos, talc, kaolin, mica,barium sulfate, metal oxides and hydroxides, carbon black, graphite,wood flour and flours or fibers of other natural products, syntheticfibers.

13. Other additives, for example, plasticisers, lubricants, emulsifiers,pigments, rheology additives, catalysts, flow-control agents, opticalbrighteners, flameproofing agents, antistatic agents and blowing agents.

14. Benzofuranones and indolinones, for example those disclosed in U.S.Pat. Nos. 4,325,863; 4,338,244; 5,175,312; 5,216,052; 5,252,643;DE-A-4316611; DE-A-4316622; DE-A-4316876; EP-A-0589839 or EP-A-0591102or 3-[4-(2-acetoxyethoxy)-phenyl]-5,7-di-tert-butyl-benzofuran-2-one,5,7-di-tert-butyl-3-[4-(2-stearoyloxyethoxy)phenyl]benzofuran-2-one,3,3′-bis[5,7-di-tert-butyl-3-(4-[2-hydroxyethoxy]phenyl)benzofuran-2-one],5,7-di-tert-butyl-3-(4-ethoxyphenyl)benzofuran-2-one,3-(4-acetoxy-3,5-dimethylphenyl)-5,7-di-tert-butyl-benzofuran-2-one,3-(3,5-dimethyl-4-pivaloyloxyphenyl)-5,7-di-tert-butyl-benzofuran-2-one,3-(3,4-dimethylphenyl)-5,7-di-tert-butyl-benzofuran-2-one,3-(2,3-dimethylphenyl)-5,7-di-tert-butyl-benzofuran-2-one.

15. Amine oxides, for example amine oxide derivatives as disclosed inU.S. Pat. Nos. 5,844,029 and 5,880,191, didecyl methyl amine oxide,tridecyl amine oxide, tridodecyl amine oxide and trihexadecyl amineoxide. U.S. Pat. Nos. 5,844,029 and 5,880,191 disclose the use ofsaturated hydrocarbon amine oxides towards the stabilization ofthermoplastic resins. It is disclosed that the thermoplasticcompositions may further contain a stabilizer or mixture of stabilizersselected from phenolic antioxidants, hindered amine light stabilizers,ultraviolet light absorbers, organic phosphorus compounds, alkalinemetal salts of fatty acids and thiosynergists. The co-use of amineoxides with other stabilizers towards stabilizing polyolefins is notexemplified.

Specific examples of additives are phenolic antioxidants (item 1 of thelist), further sterically hindered amines (item 2.6 of the list), lightstabilizers of the benzotriazole and/or o-hydroxyphenyltriazine class(items 2.1 and 2.8 of the list), phosphites and phosphonites (item 4 ofthe list) and peroxide-destroying compounds (item 5. ) of the list.

Additional specific examples of additives (stabilizers) which arebenzofuran-2-ones, such as described, for example, in U.S. Pat. Nos.4,325,863, 4,338,244 or 5,175,312.

The instant composition can additionally contain another UV absorberselected from the group consisting of the s-triazines, the oxanilides,the hydroxybenzophenones, benzoates and the α-cyanoacrylates.Particularly, the instant composition may additionally contain aneffective stabilizing amount of at least one other2-hydroxyphenyl-2H-benzotriazole; another tris-aryl-s-triazine; orhindered amine or mixtures thereof. For example, additional componentsare selected from pigments, dyes, plasticizers, antioxidants,thixotropic agents, levelling assistants, basic costabilizers, furtherlight stabilizers like UV absorbers and/or sterically hindered amines,metal passivators, metal oxides, organophosphorus compounds,hydroxylamines, and mixtures thereof, especially pigments, phenolicantioxidants, calcium stearate, zinc stearate, UV absorbers of the2-(2′-hydroxyphenyl)benzotriazole and 2-(2-hydroxyphenyl)-1,3,5-triazineclasses, and sterically hindered amines.

The additives of the invention and optional further components may beadded to the polymer material individually or mixed with one another. Ifdesired, the individual components can be mixed with one another beforeincorporation into the polymer for example by dry blending, compactionor in the melt. Subject of the invention therefore is also a flameretardant additive combination comprising

-   -   (i) at least one melamine based flame retardant and    -   (ii) at least one flame retardant selected from the group        consisting of the organohalogen and the phosphorus containing        flame retardants.

Conveniently, the additives of above components (i) and (ii) andpossibly further additives as described above may be dry blended andthen extruded, for instance in a twin screw extruder at 180–220° C.,with or without nitrogen atmosphere. The material thus obtained may befurther processed according to known methods. The surface of thearticles formed do not show any loss of gloss or any kind of roughness.

Further, the instant invention pertains to a process for imparting flameretardancy to an organic polymer substrate, which process comprisesadding to said polymer substrate an effective flame retarding amount ofa mixture of

-   -   (i) at least one melamine based flame retardant and    -   (ii) at least one flame retardant selected from the group        consisting of the organohalogen and the phosphorus containing        flame retardants.

The incorporation of the additives of the invention and optional furthercomponents into the polymer is carried out by known methods such as dryblending in the form of a powder, or wet mixing in the form ofsolutions, dispersions or suspensions for example in an inert solvent,water or oil. The additives of the invention and optional furtheradditives may be incorporated, for example, before or after molding oralso by applying the dissolved or dispersed additive or additive mixtureto the polymer material, with or without subsequent evaporation of thesolvent or the suspension/dispersion agent. They may be added directlyinto the processing apparatus (e.g. extruders, internal mixers, etc),e.g. as a dry mixture or powder or as solution or dispersion orsuspension or melt.

The incorporation can be carried out in any heatable container equippedwith a stirrer, e.g. in a closed apparatus such as a kneader, mixer orstirred vessel. The incorporation is for example carried out in anextruder or in a kneader. It is immaterial whether processing takesplace in an inert atmosphere or in the presence of oxygen.

The addition of the additive or additive blend to the polymer can becarried out in all customary mixing machines in which the polymer ismelted and mixed with the additives. Suitable machines are known tothose skilled in the art. They are predominantly mixers, kneaders andextruders.

The process is for instance carried out in an extruder by introducingthe additive during processing.

Specific examples of suitable processing machines are single-screwextruders, contrarotating and corotating twin-screw extruders,planetary-gear extruders, ring extruders or cokneaders. It is alsopossible to use processing machines provided with at least one gasremoval compartment to which a vacuum can be applied.

Suitable extruders and kneaders are described, for example, in Handbuchder Kunststoffextrusion, Vol. 1 Grundlagen, Editors F. Hensen, W Knappe,H. Potente, 1989, pp. 3–7, ISBN:3-446-14339-4 (Vol. 2 Extrusionsanlagen1986, ISBN 3-446-14329-7).

For example, the screw length is 1–60 screw diameters, for example 35–48screw diameters. The rotational speed of the screw is for instance10–600 rotations per minute (rpm), for example 25–300 rpm.

The maximum throughput is dependent on the screw diameter, therotational speed and the driving force. The process of the presentinvention can also be carried out at a level lower than maximumthroughput by varying the parameters mentioned or employing weighingmachines delivering dosage amounts.

If a plurality of components are added, these can be premixed or addedindividually.

The additives of the invention and optional further additives can alsobe sprayed onto the polymer material. They are able to dilute otheradditives (for example the conventional additives indicated above) ortheir melts so that they can be sprayed also together with theseadditives onto the material. Addition by spraying during thedeactivation of the polymerization catalysts is particularlyadvantageous; in this case, the steam evolved may be used fordeactivation of the catalyst. In the case of spherically polymerizedpolyolefins it may, for example, be advantageous to apply the additivesof the invention, optionally together with other additives, by spraying.

The additives of the invention and optional further additives can alsobe added to the polymer in the form of a masterbatch (“concentrate”)which contains the components in a concentration of, for example, about1% to about 40%, for example about 2% to, about 20% by weightincorporated in a polymer. The polymer must not be necessarily ofidentical structure than the polymer where the additives are addedfinally. In such operations, the polymer can be used in the form ofpowder, granules, solutions, suspensions or in the form of latices.

Incorporation can take place prior to or during the shaping operation.The materials containing the additives of the invention described hereinare for example used for the production of molded articles, for examplerotomolded articles, injection molded articles, profiles and the like.Thus, a molded polymer article made flame retardant by the incorporationof

-   -   (i) at least one melamine based flame retardant and    -   (ii) at least one flame retardant selected from the group        consisting of the organohalogen and the phosphorus containing        flame retardants is another object of the invention.

It is also contemplated that PTFE, polytetrafluoroethylene (for exampleTeflon® 6C; E. I. Du Pont), may be advantageously added to the presentcompositions as an additional flame retardant, as disclosed in U.S.application Ser. No. 60/312,517, filed Aug. 15, 2001.

The polyolefin molded articles of this invention may be used for exampleas roofing membranes, siding, window profiles and moldings. Such moldedarticles are for example about 5 mil to about 100 mil thick, for exampleabout 20 mil to about 100 mil thick, for instance about 10 mil to about80 mil for example about 40 mil to about 100 mil thick. The polyolefinis in particular thermoplastic olefin (TPO).

The effective flame retarding amount of component (b) is that needed toshow flame retarding efficacy as measured by one of the standard methodsused to assess flame retardancy. These include UL 1694 Tests forFlammability of Small Polymeric Component Materials, 2002; NFPA 701Standard Methods of Fire Tests for Flame-Resistant Textiles and Films,1989 and 1996 and 1999 editions; the UL 94 Test for Flammability ofPlastic Materials for Parts in Devices and Appliances, 5th Edition, Oct.29, 1996; Limiting Oxygen Index (LOI), ASTM D-2863; and ConeCalorimetry, ASTM E-1354. Ratings according to the UL 94 V test are ascompiled in the following table:

Afterflame Burning Burn to Rating time drips Clamp V-0 <10 s no no V-1<30 s no no V-2 <30 s yes no Fail <30 s yes Fail >30 s no

Coadditives found particularly useful for use with the instantcombination of components (i) and (ii) in flame retardant compositionsare as follows:

UV Absorbers:

-   -   2-(2-hydroxy-3,5-di-α-cumylphenyl)-2H-benzotriazole, (TINUVIN®        234, Ciba Specialty Chemicals Corp.);    -   2-(2-hydroxy-5-methylphenyl)-2H-benzotriazole; (TINUVIN® P, Ciba        Specialty Chemicals Corp.);    -   5-chloro-2-(2-hydroxy-3,5-di-tert-butylphenyl)-2H-benzotriazole,        (TINUVIN® 327, Ciba Specialty Chemicals Corp.);    -   2-(2-hydroxy-3,5-di-tert-amylphenyl)-2H-benzotriazole, (TINUVIN®        328, Ciba Specialty Chemicals Corp.);    -   2-(2-hydroxy-3α-cumyl-5-tert-octylphenyl)-2H-benzotriazole,        (TINUVIN® 928, Ciba Specialty Chemicals Corp.);    -   2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate,        (TINUVIN® 120, Ciba Specialty Chemicals Corp.);    -   2-hydroxy-4-n-octyloxybenzophenone, (CHIMASSORB® 81, Ciba        Specialty Chemicals Corp.);    -   2,4-bis(2,4-dimethyphenyl)-6-(2-hydroxy-4-octyloxyphenyl)-s-triazine,        (CYASORB® 1164, Cytec).

The following examples are meant for illustrative purposes only and arenot to be construed to limit the scope of this invention in any mannerwhatsoever. Where given, room temperature depicts a temperature in therange 20–25° C. Percentages are by weight of the polymer substrateunless otherwise indicated.

Abbreviations:

v parts by volume w parts by weight ¹Hnmr nuclear magnetic resonance(NMR) of ¹H m/z mass spectrometry (atomic units) amu molecular weight ing/mol (= atomic units) PP polypropylene PE polyethylene PE-LD lowdensity polyethylene (LDPE)Test Methods

-   -   NFPA 701 Standard Methods of Fire Tests for Flame-Resistant        Textiles and Films, 1989 and 1996 editions;    -   UL 1694 Tests for Flammability of Small Polymeric Component        Materials, 2002;

UL 94 Test for Flammability of Plastic Materials for Parts in Devicesand Appliances, 5th Edition, Oct. 29, 1996;

-   -   Limiting Oxygen Index (LOI), ASTM D-2863;    -   Cone Calorimetry, ASTM E-1 or ASTM E 1354;    -   ASTM D 2633-82, burn test.        Test Compounds

-   Melamine based flame retardants of component (i):

-   melamine cyanurate, MELAPUR® MC,

-   melamine borate,

-   melamine phosphate, MELAPUR® P 46,

-   melamine polyphosphate MELAPUR® 200,

-   melamine pyrophosphate,

-   melamine ammonium polyphosphate and

-   melamine ammonium pyrophosphate.

Flame retardants of component (ii):

-   FR1 tris[3-bromo-2,2-bis(bromomethyl)propyl]phosphate, (PB 370®, FMC    Corp.),-   FR2 ammonium polyphosphate (APP),-   FR3 bis(2,3-dibromopropyl)ether of tetrabromobisphenol A (PE68),-   FR4 ammonium polyphosphate/synergist blend, HOSTAFLAM® AP750,-   FR5 decabromodiphenyl oxide (DBDPO; obtained from Dead Sea Bromine),-   FR6 ethylene bis-(tetrabromophthalimide), (SAYTEX® BT-93),-   FR7 ammonium polyphosphate, EXOLIT® AP752,-   FR8 tris-(2,3-dibromopropyl)-isocyanurate,-   FR9 hexabromocyclododecane,

Hindered Amines:

-   -   NOR1        1-cyclohexyloxy-2,2,6,6-tetramethyl-4-octadecylaminopiperidine;    -   NOR2 bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate;    -   NOR3        2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-(2-hydroxyethylamino-s-triazine;    -   NOR4        2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-chloro-s-triazine;    -   NOR5        1-(2-hydroxy-2-methylpropoxy)-4-hydroxy-2,2,6,6-tetramethylpiperidine;    -   NOR6        1-(2-hydroxy-2-methylpropoxy)-4-oxo-2,2,6,6-tetramethylpiperidine;    -   NOR7        1-(2-hydroxy-2-methylpropoxy)-4-octadecanoyloxy-2,2,6,6-tetramethylpiperidine;    -   NOR8        bis(1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl)sebacate;    -   NOR9        bis(1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl)adipate;    -   NOR10        2,4-bis{N-[1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl]-N-butylamino}-6-(2-hydroxyethylamino)-s-triazine;    -   NOR11 the reaction product of        2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetrmethylpiperidin-4-yl)butylamino]-6-chloro-s-triazine        with N,N′-bis(3-aminopropyl)ethylenediamine) [CAS Reg. No.        191680-81-6];    -   NOR11 is represented as a mixture of compounds with main        component of the formula        R₁NH—CH₂CH₂CH₂NR₂CH₂CH₂NR₃CH₂CH₂CH₂NHR₄        -   wherein 3 of R₁, R₂, R₃ and R₄ are residues of formula

 and 1 of R₁, R₂, R₃ and R₄ is hydrogen

-   -   -   (NOR11 is a high molecolar weight compound disclosed in            example 3 of U.S. Pat. No. 5,844,026);

    -   NOR12 the compound of formula

in which n is from 1 to 15; and

-   -   NOR13 bis(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)        adipate.

Compounds NOR2, NOR7, NOR11, NOR12 are commercial stabilizers availablefrom Ciba Specialty Chemicals. MELAPUR products are available from CibaSpecialty Chemicals.

EXAMPLE 1

Flame Retardant Polypropylene

Additives are dry mixed and extruded with polypropylene homopolymerresin with a twin screw (27 mm) extruder at 200° C. under nitrogen. Fromthe pellets, 1.6 mm plaques are prepared by injection molding. Theplaques are tested according to UL 94 protocol after 48 hoursconditioning at 25° C. and 50% humidity and also after 7 days at 70° C.UL 94 ratings are the same for both exposures. The plaques are alsotested according to UL 1694 protocol after 48 hours at 25° C. and 50%humidity and also after 24 hours at 70° C. UL 1694 ratings are the samefor both exposures. Weight percent of additives and flame retardantresults are in the table below. Weight percents are based on thepolymer.

melamine cyanurate FR3 Sb₂O₃ UL 94 rating UL 1694 rating — 8 3 V-0 fail— 4 2 V-2 fail 4 8 3 V-0 pass 6 6 2 V-0 pass 8 4 2 V-0 fail

The additional inclusion of a hindered amine selected from NOR1–NOR13provides further flame retardancy as well as light stability.

Melamine cyanurate may be replaced with a flame retardant selected fromthe group consisting of melamine borate, melamine phosphate, melaminepolyphosphate, melamine pyrophosphate, melamine ammonium polyphosphateand melamine ammonium pyrophosphate with good results.

FR1 and FR3 may be replaced with another flame retardant selected fromFR1–FR9 with good results.

EXAMPLE 2

Polypropylene-Ethylene Copolymer

Sample preparation: Polymer powder and stabilizers are pre-mixed(Henschel mixer, 800 rpm, room temperature), pigment powder and flameretardant are added as concentrate in PP and homogenized in a drummixer. Further homogenization and granulation is achieved by extrusion(Collin® twin screw extruder, max 200° C., 100 rpm). Subsequently, themixture is processed into a flat film by means of a single screwextruder (max 200° C., 70 rpm) equipped with a corresponding nozzle(sample dimension 2 mm thickness, 10 cm width).

Weathering: Punched samples are exposed to accelerated weathering(Atlas® WOM Ci 65, 0.35 W/m² (at 340 nm), 102 min dry, 18 min waterspray, 63° C. black panel temperature. The effect of weathering on thesurface is assessed in the following manner:

-   Visual inspection of chalking (chalking indicates decomposition on    the surface).-   Gloss: Minolta; degradation of surface reduces the reflection of    polarized light (60° gloss as defined in DIN 67530).-   Δ E: Color change (according to DIN 6174).

Formulation:

-   84 parts by weight of polypropylene-ethylene copolymer (Novolen® PPG    1022),-   15 parts by weight of a PE-based flame retardant masterbatch    containing 51% by weight of a 1:1 mixture of FR1 and melamine    cyanurate-   1 part by weight of TiO₂ and-   0.2 parts by weight of blue pigment (Cromophtal blue 4GNP)

Excellent flame retardant results are obtained.

Melamine cyanurate may be replaced with a flame retardant selected fromthe group consisting of melamine borate,melamine phosphate, melaminepolyphosphate, melamine pyrophosphate, melamine ammonium polyphosphateand melamine ammonium pyrophosphate with good results.

FR1 may be replaced with another flame retardant selected from FR1–FR9with good results.

EXAMPLE 3

TPO Roofing Membranes

The polyolefin molded articles of this invention may be used for exampleas roofing membranes, siding, window profiles and moldings. Such moldedarticles are for example about 5 mil to about 100 mil thick. Thepolyolefin is in particlular thermoplastic polyolefin (TPO). The moldedarticles of this invention exhibit flame retardant properties.

A typical state of the art formulation for such applications is forexample:

parts Polypropylene copolymer 100 TiO₂ or carbon black 3 CaCo₃ 5Magnesium hydroxide 35 UV stabilizer 1 Lubricant or other 1

The state of the art formulation requires that either TiO₂ or carbonblack are present and that magnesium hydroxide is present.

The formulation of the present invention is for example:

parts Polypropylene copolymer 100 TiO₂ or carbon black 3 CaCO₃ 0–5Magnesium hydroxide 0 NOR7 1.0 FR1 4 melamine cyanurate 6 UV stabilizer1 Present acid scavenger 1

NOR7 may be replaced for example with another hindered amine selectedfrom NOR1–NOR13. FR1 may be replaced with a flame retardant selectedfrom FR2–FR9. Excellent results are achieved.

Melamine cyanurate may be replaced with a flame retardant selected fromthe group consisting of melamine borate, melamine phosphate, melaminepolyphosphate, melamine ammonium polyphosphate, melamine ammoniumpyrophosphate and melamine pyrophosphate with good results.

EXAMPLE 4

Polyethylene fibers are prepared from fiber grade polyethylene by dryblending with test additives and melt compounding at 400° F. Fibers areextruded from this formulation using a Hills laboratory scale fiberextruder. Socks are knitted from the fibers and are tested for flameretardancy according to NFPA 701 vertical burn method. Polyethylenefibers contain 12% by weight of a 1:1 mixture of a melamine based flameretardant and a flame retardant selected from FR1–FR9 and 0.5%, 1% or 2%by weight, total, of an additive selected from NOR1–NOR13. Theseformulated fibers are tested for flame retardancy according to NFPA 701.

The fibers containing a melamine based flame retardant, and a flameretardant selected from FR1–FR9 exhibit excellent flame retardancy.

EXAMPLE 5

Foam grade polyethylene is dry blended with test additives and then meltcompounded into pellets. The pelletized fully formulated resin is thenblown into foam.

The polyethylene foam prepared contains an instant additive selectedfrom the melamine based flame retardants and a flame retardant FR1–FR9.The formulated foam is tested for flame retardancy according to theUL-94 burn test method.

The foam containing a melamine based flame retardant and a flameretardant selected from FR114 FR9 exhibits excellent flame retardancy.

EXAMPLE 6

Wire & cable grade polyethylene is dry blended with test additives andthen melt compounded into pellets. The pelletized fully formulated resinis then extruded onto wire.

Test specimens are tested for flame retardancy using the ASTM D 2633-82burn test conditions. The formulations containing a melamine based flameretardant, a flame retardant selected from FR1–FR9 and optionally acompound selected from NOR1–NOR13 exhibit excellent flame retardancy.

EXAMPLE 7

Fiber grade polyethylene is dry-blended with test additives. Non-wovenfabrics are produced from the polymer blend formulations by aspun-bonded or melt-blown process.

The non-woven fabrics made thereby are tested for flame retardancyaccording to the NFPA 701 vertical burn test specifications. The fabricscontaining a melamine based flame retardant and a flame retardantselected from FR1–FR9 exhibit excellent flame retardancy.

EXAMPLE 8

Fiber grade polypropylene is dry-blended with test additives. Non-wovenfabrics are produced from the polymer blend formulations by aspun-bonded or melt-blown process.

The non-woven fabrics made thereby are tested for flame retardancyaccording to the NFPA 701 vertical burn test specifications. The fabricscontaining a melamine based flame retardant and a flame retardantselected from FR1–FR9 exhibit excellent flame retardancy.

EXAMPLE 9

Molding grade polystyrene is dry-blended with test additives and thenmelt compounded. Specimens are injection molded from these testformulations.

The specimens are tested for flame retardancy according to the UL-94burn test specifications. The molded specimens containing a melaminebased flame retardant and a flame retardant selected from FR1–FR9exhibit excellent flame retardancy.

EXAMPLE 10

Foam grade polystyrene is dry-blended with test additives and then meltcompounded. Foam polystyrene-specimens are prepared from these testformulations.

The specimens are tested for flame retardancy according to the UL-94burn test specifications. The foam specimens containing a melamine basedflame retardant and a flame retardant selected from FR1–FR9 exhibitexcellent flame retardancy.

EXAMPLE 11

Molding grade ABS is dry blended with test additives and then meltcompounded at 425° F. (218° C.). Specimens 125 mil (⅛″) thick are theninjection molded from this formulation using a Boy Injection Molder at450° F. (232° C.). The specimens are tested for flame retardancyaccording to the UL-94 vertical burn test specifications.

The specimens containing a melamine based flame retardant and a flameretardant selected from FR1–FR9 exhibit excellent flame retardancy.

EXAMPLE 12

Fiber grade polypropylene is dry blended with test additives and thenmelt compounded at 234° C. (450° F.) into pellets. The pelletized fullyformulated resin is then spun at 246° C. (475° F.) into fiber using aHills laboratory model fiber extruder. The spun tow of 41 filaments isstretched at a ratio of 1:3.2 to give a final denier of 615/41.

Socks are knitted from the stabilized polypropylene fiber on aLawson-Hemphill-Analysis Knitter and tested under NFPA 701 vertical burnprocedure. The time in seconds for the knitted sock to extinguish afterthe insult flame is removed is reported as “After Flame”. Both themaximum time for any one replicate and the total time for ten replicatesare measured. Efficacy as a flame retardant is demonstrated when lowAfter Flame times are observed relative to a blank sample containing noflame retardant.

The specimens containing a melamine based flame retardant and a flameretardant selected from FR1–FR9 exhibit excellent flame retardancy.

EXAMPLE 13

Film grade polyethylene is dry blended with test additives and then meltcompounded into pellets. The pelletized fully formulated resin is thenblown at 205° C. using a MPM Superior Blown film extruder.

The films are tested for flame retardancy under NFPA 701 testconditions. The specimens containing a melamine based flame retardantand a flame retardant selected from FR1–FR9 exhibit excellent flameretardancy.

Film grade polypropylene is handled in a similar fashion andpolypropylene films containing the present additive combinations alsoshow excellent flame retardancy.

EXAMPLE 14

Molded test specimens are prepared by injection molding thermoplasticolefin (TPO) pellets containing a present additive combination. The TPOformulations may also contain a pigment, a phosphite; a phenolicantioxidant or hydroxylamine, a metal stearate, a UV absorber or ahindered amine stabilizer or a mixture of hindered amine and UVabsorber.

Pigmented TPO formulation composed of polypropylene blended with arubber modifier where the rubber modifier is an in-situ reactedcopolymer or blended product containing copolymers of propylene andethylene with or without a ternary component such as ethylidenenorbornene are stabilized with a base stabilization system consisting ofan N,N-dialkylhydroxyl-amine or a mixture of hindered phenolicantioxidant and an organophosphorus compound.

The TPO plaques are tested for flame retardancy using the UL-94 VerticalBurn conditions. A minimum of three replicates are tested. Efficacy as aflame retardant is measured relative to a blank sample containing noflame retardant.

The specimens containing a melamine based flame retardant and a flameretardant selected from FR1–FR9 exhibit excellent flame retardancy.

EXAMPLE 15

Film grade ethylene/vinyl acetate (EVA) copolymers containing 20 weightpercent or less of vinyl acetate are dry blended with test additives andthen melt compounded into pellets. The pelletized fully formulated resinis then blown into a film at 205° C. using a MPM Superior Blown-filmextruder.

The films are tested for flame retardancy under NFPA 701 testconditions. The films containing a melamine based flame retardant and aflame retardant selected from FR1–FR9 exhibit excellent flameretardancy.

Film grade low density polyethylene (LDPE) which contains some linearlow density polyethylene (LLDPE) and/or ethylene/vinyl acetate (EVA) aredry blended with test additives and blown into film as described abovefor EVA copolymer resin. The films are tested for flame retardancy underNFPA 701 test conditions and those containing a melamine based flameretardant and a flame retardant selected from FR1–FR9 exhibit excellentflame retardancy.

EXAMPLE 16

High impact polystyrene (HIPS) polymer (STYRON® 484C, Dow Chemical Co.)is compounded with test additives, pelletized and then injection orcompression molded into plaques. These plaques are tested for flameretardant efficacy using cone calorimetry, LOI or UL-94 test method.

The fabrics containing a melamine based flame retardant and a flameretardant selected from FR1–FR9 exhibit excellent flame retardancy.Flame retardant HIPS polymers find application in housings for businessmachines.

EXAMPLE 17

This Example shows the efficacy of the present compound combinations inPVC formulations. Such formulations are useful in flexible or rigid PVCand in wire and cable applications.

Typical formulations are seen below:

Component parts parts parts parts PVC resin 100 100 100 100 tinmercaptide 1.5 — 2.0 — tin carboxyate — 2.5 — 2.0 process aid 1.5 1.52.0 2.0 impact mod. 6.0 6.0 7.0 7.0 paraffin wax 1.0 0.3 1.0 1.0polyethyl wax 0.1 0.1 0.2 0.2 Ca stearate 1.0 — 0.8 — pigment 1.0 0.95.0 5.0

Fully formulated PVC containing a melamine based flame retardant and aflame retardant selected from FR1–FR9 is pelletized and then injectionmolded into test plaques for examination of flame retardancy using theUL-94 or LOI test method.

The PVC plaques containing the instant compound combinations demonstrateexcellent flame retardancy.

EXAMPLE 18

Fiber grade poly(ethylene terephthalate) (PET) is dry blended with testadditives, then melt compounded at 550° F. and then pelletized. Thepolyester pellets are dried at 175° F. for 24 hours under vacuum. Thedried pellets are extruded into fibers using a Hills laboratory scalefiber extruder at 550° F. Socks are knitted from these fibers and testedfor flame retardancy according to NFPA 701 test method.

The fibers containing a melamine based flame retardant and a flameretardant selected from FR1–FR9 exhibit excellent flame retardancy.

EXAMPLE 19

Thermoplastic resins including polypropylene, polyethylene homopolymer,polyolefin copolymer or thermoplastic olefins (TPO), high impactpolystyrene (HIPS) and ABS are dry blended with test additives and thenmelt compounded into pellets. The pelletized fully formulated resin isthen processed into a useful article such as extrusion into fiber; blownor cast extrusion into film; blow molded into bottles; injection moldedinto molded articles, thermoformed into molded articles, extruded intowire and cable housing or rotation molded into hollow articles.

The articles containing a melamine based flame retardant and a flameretardant selected from FR1–FR9 exhibit excellent flame retardancy whentested by a known standard test method.

Polyethylene wire and cable applications are tested for flame retardancyaccording to ASTM D-2633-82 burn test method. The materials containing amelamine based flame retardant and a flame retardant selected fromFR1–FR9 exhibit excellent flame retardancy.

EXAMPLE 20

Articles prepared according to Example 19 which additionally contain anorganophosphorus stabilizer selected from the group consisting oftris(2,4-di-tert-butylphenyl) phosphite,bis(2,4-di-tert-butyl-6-methylphenyl)ethyl phosphite,2,2′,2″-nitrilo[triethyl-tris-(3,3′,5,5′-tetra-tert-butyl-1,1′-biphenyl-2,2′-diyl)phosphite],tetrakis(2,4-di-butylphenyl) 4,4′-biphenylenediphosphonite,tris(nonylphenyl) phosphite, bis(2,4-di-tert-butylphenyl)pentaerythrityl diphosphite, 2,2′-ethylidenebis(2,4-di-tert-butylphenyl)fluorophosphite and 2-butyl-2-ethylpropan-1,3-diyl2,4,6-tri-tert-butylphenyl phosphite exhibit good flame retardancyproperties.

EXAMPLE 21

Articles prepared according to Example 19 which additionally contain ao-hydroxy-phenyl-2H-benzotriazole, a hydroxyphenyl benzophenone or ao-hydroxyphenyl-s-triazine UV absorber selected from the groupconsisting of 2-(2-hydroxy-3,5-di-α-cumylphenyl)-2H-benzotriazole,2-(2-hydroxy-5-methylphenyl)-2H-benzotriazole,5-chloro-2-(2-hydroxy-3,5-di-tert-butyl-phenyl)-2H-benzotriazole,2-(2-hydroxy-3,5-di-tert-amylphenyl)-2H-benzotriazole,2-(2-hydroxy-3-α-cumyl-5-tert-octylphenyl)-2H-benzotriazole,2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate,2-hydroxy-4-n-octyloxybenzophenone and2,4-bis(2,4-dimethyphenyl)-6-(2-hydroxy-4-octyloxyphenyl)-s-triazineexhibit good flame retardancy.

EXAMPLE 22

Polypropylene Electrical Insulation

Polypropylene homopolymer samples are prepared.

The samples containing a melamine based flame retardant and a flameretardant selected from FR1–FR9 exhibit excellent flame retardancy whentested by a known standard test method.

Test method UL 1694, Tests for Flammability of Small Polymeric ComponentMaterials, is relevant for this application.

EXAMPLE 23

Polyethylene Electrical Parts

Polyethylene electrical parts, HDPE and LDPE, are prepared.

The parts containing a melamine based flame retardant and a flameretardant selected from FR1–FR9 exhibit excellent flame retardancy whentested by a known standard test method.

Test method NFPA 701 is relevant.

EXAMPLE 24

Polystyrene Electrical Parts

Example 23 is repeated with polystyrene electrical parts.

The samples containing a melamine based flame retardant and a flameretardant selected from FR1–FR9 exhibit excellent flame retardancy whentested by a known standard test method.

Test methods UL 94 and UL 1694 are relevant.

1. A flame retardant polyolefin composition which comprises (a) apolyolefin polymer and (b) an effective flame retarding amount of amixture of (i) melamine cyanurate and (ii) bis(2,3-dibromopropyl ether)of tetrabromobisphenol A and where the composition comprises no organicradical sources of the formula

where R=CH₃ or C₂H₅, R′=CH₃ and R″=C₆H₅ and wherein the compositionmeets a UL 94 rating of V0 and a UL 1694 rating of passing, and wherethe weight ratio of component (i) to component (ii) is between 10:1 to1:10.
 2. A composition according to claim 1 in which the polyolefinpolymer is polyethylene, polypropylene or propylene/ethylene copolymer.3. A composition according to claim 1 further comprising flame retardantfillers, conventional fillers or nano-scaled fillers.
 4. A compositionaccording to claim 1 further comprising antimony compounds.
 5. Acomposition according to claim 1 which further comprises at least onesterically hindered amine stabilizer.
 6. A composition according toclaim 1 further comprising antimony compounds and at least onesterically hindered amine stabilizer.
 7. A composition according toclaim 5 where the sterically hindered amine stabilizers are selectedfrom the group consisting of 1-cyclohexyloxy-22,6,6-tetramethyl-4-octadecylaminopiperidine;bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate;2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-(2-hydroxyethylamino-s-triazine;bis(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)adipate;2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-chloro-s-triazine;1-(2-hydroxy-2-methylpropoxy)-4-hydroxy-2,2,6,6-tetramethylpiperidine;1-(2-hydroxy-2-methylpropoxy)-4-oxo-2,2,6,6-tetramethylpiperidine;1-(2-hydroxy-2-methylpropoxy)-4-octadecanoyloxy-2,2,6,6-tetramethylpiperidine;bis(1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl)sebacate;bis(1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl)adipate;2,4-bis{N-[1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl]-N-butylamino}-6-(2-hydroxyethylamino)-s-triazine;the reaction product of2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetrmethylpiperidin-4-yl)-butylamino]-6-chloro-s-triazinewith N,N′-bis(3-aminopropyl)ethylenediamine) and the compound of formula

in which n is from 1 to
 15. 8. A composition according to claim 1 inwhich the flame retarding mixture of component (b) is present in anamount from about 0.5% to about 45% by weight based on the polymersubstrate (a).
 9. A composition according to claim 1 in which the flameretarding mixture of component (b) is present in an amount from about0.5% to about 15% by weight based on component (a).
 10. A compositionaccording to claim 1 comprising a further component selected from thegroup consisting of pigments, dyes, plasticizers, phenolic antioxidants,thixotropic agents, levelling assistants, basic costabilizers, nitronestabilizers, amine oxide stabilizers, benzofuranone stabilizers, UVabsorbers, sterically hindered amines, metal passivators, metal oxides,organophosphorus compounds, hydroxylamines, and mixtures thereof.
 11. Acomposition according to claim 10 in which the further component isselected from the group consisting of phenolic antioxidants, calciumstearate, zinc stearate, phosphite or phosphonite stabilizers,benzofuranone stabilizers, UV absorbers of the2-(2′-hydroxyphenyl)benzotriazole or 2-(2-hydroxyphenyl)-1,3,5-triazineclasses, and sterically hindered amines.
 12. A molded polyolefin articleproduced from the composition according to claim
 1. 13. A molded articleaccording to claim 12 which is a construction article selected from thegroup consisting of roofing membranes, window profiles, siding andmoldings or which is an electrical part selected from the groupconsisting of plugs, sockets and wire insulation.
 14. A molded articleaccording to claim 12 where the polyolefin is polypropylene,polyethylene, propylene/ethylene copolymer or thermoplastic olefin. 15.A molded article according to claim 12 which further comprises flameretardant fillers, conventional fillers or nano-scaled fillers.
 16. Amolded article according to claim 12 which further comprises antimonycompounds.
 17. A molded article according to claim 12 further comprisingat least one sterically hindered amine stabilizer.
 18. A molded articleaccording to claim 12 further comprising antimony compounds and at leastone sterically hindered amine stabilizer.
 19. A process for impartingflame retardancy to a polyolefin substrate, which process comprisesadding to said substrate (i) melamine cyanurate and (ii)bis(2,3-dibromopropyl ether) of tetrabromobisphenol A wherein no organicradical sources of the formula

where R=CH₃ or C₂H₅, R′=CH₃ and R″=C₆H₅, are added and and wherein theflame retardant substrate meets a UL 94 rating of V0 and a UL 1694rating of passing, and where the weight ratio of component (i) tocomponent (ii) is between 10:1 to 1:10.